Multi Color Sapphire Ring Style Locket.

Multi Color Sapphire Ring Style Locket. 

By Stone.

Upon heating, the stone becomes more blue in color, but loses some of the rutile inclusions (silk). When high temperatures are used, the stone loses all silk (inclusions) and it becomes clear under magnification. The inclusions in natural stones are easily seen with a jeweler's loupe. Evidence of sapphire and other gemstones being subjected to heating goes back at least to Roman time